underline-motion(n)
    if n == 'link'
        background-image linear-gradient($color-background, $color-background), linear-gradient($color-text-primary, $color-text-primary)
        background-size 100% $line-third, 0% $line-third
        background-position 100% 100%, 0 100%
        background-repeat no-repeat, no-repeat
        transition background-size .6s linear

        &:hover 
            background-size 0 $line-third, 100% $line-third

    else if n == 'underline-link'
        padding-bottom $line-secondary
        background-image linear-gradient($color-text-primary, $color-text-primary), linear-gradient($color-text-primary, $color-text-primary)
        background-size 100% $line-third, 0 $line-secondary
        background-position 100% 100%, 0 100%
        background-repeat no-repeat, no-repeat
        transition background-size .6s linear

        &:hover 
            background-size 100% $line-third, 100% $line-secondary

    else if n == 'header'
        &:after
            content ""
            -webkit-transition width .4s ease-in-out
            transition width .4s ease-in-out
            position absolute
            left 0
            bottom 0
            width 0
            border-bottom solid $line-third $color-text-primary

        &:hover:after
            width 100%
